AgentCall vs AgentPhone: Which Phone API for AI Agents? [2026]

Short answer: pick AgentPhone if you need iMessage, browser-based web calls, isolated sub-accounts for resale, a Python SDK, or the lowest possible per-minute voice cost. Pick AgentCall if you want the phone agent to actually work without you building the brain: a hosted MCP server your AI connects to over a URL, cross-call memory that remembers a caller between calls, tool calling from the hosted AI so it can check a real price or a real calendar, and prompt-driven AI texting. AgentPhone is cheaper per AI voice minute ($0.22 vs $0.40 managed). AgentCall is cheaper to get to a working agent, because with AgentPhone the intelligence is your job.

Both products use the same positioning phrase, “phone numbers for AI agents,” which makes them look interchangeable in a search result. They are not. This post lays out what each one actually ships, with real numbers, and it concedes the places where AgentPhone is the better buy.

What AgentPhone Is

AgentPhone (agentphone.ai, legally Relay Innovations Inc.) is a Y Combinator backed phone API that launched around May 2026. It was founded by two brothers, one of whom worked on business agent messaging infrastructure at Meta. It sells US and Canada numbers with voice, SMS, and iMessage, and it is very good at the plumbing layer. The messaging surface in particular is the most complete of any phone API aimed at agents right now.

Their design centre is: we give you excellent pipes, you bring the intelligence. Their hosted voice mode takes a prompt and talks. If you want the agent to do anything beyond talking, you switch to webhook mode and host the entire model loop yourself.

What AgentCall Is

AgentCall sells the same primitive (a real US or Canada number an AI agent can own) but the product ships the intelligence with it. The managed AI answers calls and texts from a system prompt, remembers callers across calls with citable evidence, calls your tools mid conversation, extracts one-time passcodes out of inbound SMS, and exposes all of it to Claude, Cursor, Windsurf, and Codex through a hosted MCP server at a URL. There is more on the primitive itself in Why AI Agents Need Phone Numbers.

AgentCall vs AgentPhone Feature Comparison

AgentPhone Pricing vs AgentCall Pricing: A Worked Example

Take a small support line: one number, 200 minutes of AI voice, and 500 SMS in a month.

AgentPhone: $3.00 for the number, plus 200 minutes at $0.22 hosted ($44.00), plus 500 messages at $0.02 ($10.00). Roughly $57/mo.

AgentCall Pro: $19.99 base, plus $2.00 for the local number, plus 200 minutes at $0.40 managed ($80.00), plus 500 outbound SMS at $0.015 ($7.50). Roughly $109/mo.

That is not close, and we are not going to pretend otherwise. AgentPhone's hosted voice is materially cheaper per minute than our managed voice, and they do not charge a platform fee on top. If per-minute cost is the number your decision turns on, they win it.

One caveat on the other side of the ledger. AgentCall's bring-your-own-key rate is $0.10/min, which undercuts their $0.13/min webhook rate, and you keep the managed voice pipeline (barge-in, transcripts, memory, summaries) instead of hosting the whole model loop yourself. The honest asterisk is that BYOK adds your own OpenAI spend on top of the $0.10, so the true all-in number depends on your model choice and how chatty your calls are. Same run at BYOK is roughly $49/mo before model spend. Details are at /docs/byok.

The other thing the $57 figure hides: in AgentPhone's hosted mode the agent can only talk. The moment you need it to look up a real price, read a real calendar, or write to your CRM, you are in webhook mode, hosting the model loop, paying for that compute, and maintaining it. That engineering time is the real price difference, and it does not show up on either pricing page.

Where AgentPhone Is Genuinely Ahead: iMessage and Web Calls

iMessage is the standout, and we do not match it. AgentPhone can send and receive on the blue-bubble channel with tapbacks, threaded replies, send effects, typing indicators, and group chats. For a consumer-facing agent in the US, blue bubbles read as legitimate in a way that green bubbles do not.

The compliance angle matters even more than the aesthetics. Outbound A2P texting on the regular network requires 10DLC brand and campaign registration, which is paperwork, review time, and throughput limits before your first message goes out. Outbound iMessage sidesteps that registration entirely. If you want an agent texting consumers this week rather than next month, that is a real, structural advantage.

Web calls are the second one. AgentPhone lets a visitor talk to your agent from a browser with no phone number involved. If your funnel is “click to talk to the AI on our pricing page,” they have a first-class answer and we do not.

Sub-accounts are the third. If you are a platform reselling phone capability to many customers who must never see each other's data, their master-account-with-isolated-tenants model is built for exactly that shape.

Where AgentCall Is Ahead: MCP, Memory, and an AI That Can Act

A hosted MCP server, not an npx package

Both products ship MCP. The difference is where it runs. AgentPhone ships a local server you install with npx, 26 tools, on the machine running the client. AgentCall's is a URL with 60 tools and 5 prompts, so any MCP client that speaks streamable HTTP can connect without installing anything, including clients on machines you do not control. Paste this into Claude Desktop and you are done:

{
  "mcpServers": {
    "agentcall": {
      "transport": "streamable-http",
      "url": "https://api.agentcall.co/mcp",
      "headers": {
        "Authorization": "Bearer YOUR_API_KEY"
      }
    }
  }
}

Restart the client and your AI can provision a number, send a text, wait for a one-time passcode, place an AI voice call, and read the transcript back. The full client matrix (Cursor, Windsurf, VS Code, Codex) is at /docs/mcp.

Cross-call memory that cites its evidence

AgentPhone gives you a metadata blob you write and maintain yourself, plus a summary after each call. That is a log, not a memory. Nothing in the product recognises a repeat caller and brings forward what they said last time.

AgentCall builds a per-caller memory automatically, keeps the transcript line each fact came from so you can audit why the agent believes something, and loads it onto the next call before the agent speaks. A customer who called on Tuesday about a broken unit does not re-explain it on Friday. That is the difference between a phone API and a phone agent, and it is covered in depth on the cross-call memory page.

Tool calling and AI SMS from the hosted side

This is the sharpest split. AgentPhone's hosted voice mode is prompt-only: it can say things, it cannot do things. To give it a live price lookup or a calendar write you leave hosted mode and host the model loop. And per their own docs, SMS is always webhook-based regardless of voice mode, so there is no prompt-driven AI texting at all. Every inbound text hits your server and you write the reply.

On AgentCall the hosted AI calls your tools mid-conversation on both voice and SMS. You set a system prompt, point it at your endpoints, and the agent books, quotes, and checks against real data without you running an inference loop. Add proactive scheduling (the agent can text or call first, not just react) and one-time passcode extraction, and the set of workflows that need zero backend from you gets fairly large.

Language Coverage: 31 Languages vs 63 Locales

AgentPhone advertises 63 locales. AgentCall advertises 31 languages. Those are not the same unit and it would be dishonest to present the gap as real. A locale list counts en-US, en-GB, en-AU, and en-IN as four entries where a language list counts “en” as one. Their 63 locales work out to roughly 30 to 35 distinct languages.

Treat the two as comparable. If you need a specific regional accent pinned, check their locale list. If you need a specific language covered, check our language guide. Neither product should win or lose this on the headline number.

When AgentPhone Is the Better Choice

Genuinely, pick them if any of these describe you:

• You need iMessage or blue-bubble delivery. We have no answer here and no near-term plan to. If rich consumer messaging is the product, they are the product.
• You want to skip 10DLC registration for outbound. Their iMessage path avoids it. Ours does not.
• You need browser-based voice. Talk-to-the-agent widgets on a website are a first-class feature there.
• You are reselling to many isolated tenants. Sub-accounts under one master account are exactly that shape.
• You are a Python shop. They ship a Python SDK. We ship Node.js plus a REST API and MCP, which works from Python but is not the same as a first-party client.
• Per-minute cost decides it. $0.22 hosted beats $0.40 managed, and no amount of framing changes that.
• You need phone-tree navigation or transfer to a human. DTMF keypad presses and cold transfer are shipped features there.

When AgentCall Is the Better Choice

• You want a working phone agent, not a phone API. Memory, tool calling, and AI texting are in the box.
• Your AI is the developer. A hosted MCP URL with 60 tools means Claude or Cursor can run the whole phone stack with no local install.
• Repeat callers matter. Support lines, clinics, and sales follow-up all get materially better when the agent remembers.
• The agent needs to act on real data. Live pricing, calendars, CRM writes, all from the hosted AI.
• You are automating signups. One-time passcode extraction from inbound SMS is a first-class helper.
• You want to test with a real number for $0. The free tier is a real provisioned number with no card, not a credit that burns down.
• You want to control model cost. BYOK at $0.10/min is the cheapest managed-pipeline option in this comparison.
• You expect concurrent calls early. There is no concurrency cap to run into on day one.

Two Different Design Centres

The fair summary is that these products disagree about where the intelligence lives, not about who is better at telephony.

AgentPhone built excellent pipes and assumes you bring the brain. Their messaging surface is the best in the category, their per-minute cost is lower, and their webhook mode gives you total control if you want to own the model loop. That is a coherent, well-executed product and there are plenty of teams it fits.

AgentCall ships the brain. Memory, tool calling, AI texting, and scheduling exist so that a useful phone agent runs before you write a backend. You pay more per minute for that, and you give up iMessage and web calls to get it.

If you are still unsure, the cheapest way to decide is to run both. Their $5 credit and our free number both take a few minutes and neither asks for a card. More on what we ship is at the product overview.

FAQ: AgentCall vs AgentPhone

Is AgentPhone cheaper than AgentCall?

For hosted AI voice, yes. $0.22/min against our $0.40/min managed, and they have no monthly platform fee. Our BYOK tier at $0.10/min is cheaper than their $0.13/min webhook rate, but you add your own model spend on top. On a 200-minute, 500-SMS month the totals are roughly $57 for them and $109 for AgentCall Pro.

Does AgentCall support iMessage?

No. AgentPhone does, including group chats and tapbacks, and outbound iMessage avoids 10DLC registration. If that is a requirement, they are the right choice.

Can AgentPhone's AI call my API during a call?

Not in hosted mode, which is prompt-only. You would switch to webhook mode and host the model loop yourself. AgentCall's hosted AI calls your tools directly on voice and SMS.

Which one has better AI agent tooling?

AgentCall, on the MCP axis specifically. Ours is hosted at a URL with 60 tools and 5 prompts, so any MCP client connects with a config paste. Theirs is a local npx server with 26 tools. Setup instructions are at /docs/mcp.

Do both work outside the US and Canada?

No. Both are US and Canada only for numbers today. AgentCall also offers toll-free and mobile number types, not just local.

Can I use both together?

Yes, and for some teams that is the right call: AgentPhone for the iMessage channel, AgentCall for the voice agent with memory and tool calling. The APIs are independent. Common setup questions are answered on the FAQ page.

Related Reading

• Why AI Agents Need Phone Numbers
• How to Give Your AI Agent a Phone Number That Remembers Every Call
• Cross-Call Memory for AI Phone Agents
• AgentCall MCP server setup
• Bring your own key (BYOK) pricing
• AgentCall product overview